Telecommunications connector protective device

ABSTRACT

A fiber optic connector assembly includes a fiber optic connector mounted to a fiber optic cable having a ferrule with an end face terminating an optical fiber. The fiber optic cable is terminated with the fiber optic connector in a clean environment protected against airborne contaminants. A seal is placed about the ferrule within the clean environment to protect the polished end face of the ferrule including the end of the optical fiber against airborne contaminants. The seal is removable to make a fiber optic communications linkage without cleaning the end face of the optical ferrule.

CROSS REFERENCE TO RELATED APPLICATION

This application is a divisional of application Ser. No. 10/750,380filed on Dec. 29, 2003, which application is incorporated herein byreference.

TECHNICAL FIELD

The present invention relates generally to protective devices fortelecommunications connectors.

BACKGROUND

Telecommunications cables are often pre-terminated by a manufacturer ora supplier. These pre-terminated cables may be configured to standard orcustoms lengths and may have one or both ends terminated. The connectorsattached to the ends of these cables may be susceptible to damage orcontamination during transportation from the manufacturer or supplier toa warehouse, storage facility or installation site. Damage to theseconnectors and cable ends may result in lost time to repair theconnectors as well as possible signal degradation.

Improvements to protecting the ends of telecommunications cableconnectors are desirable.

SUMMARY

The present invention relates to a cover assembly for a fiber opticconnector mounted to an end of and terminating a fiber optic cable. Thecover includes an open sided box and a lid sized to engage the openside. The box and the lid define a cavity sized to fit about and receivea fiber optic connector. The cavity has an open end adapted to receivethe optical fiber cable. The fiber optic connector is held within thecavity and the cable extends through the open end, with the lid engagingthe open side and sealing the cavity from contaminants outside thecavity.

Further, the present invention relates to a fiber optic connectorassembly with a fiber optic connector mounted to a fiber optic cable andincluding a ferrule with an end face terminating the fiber. A plug isconfigured to fit about and engage the ferrule of the fiber opticconnector to seal the end face from contaminants. An adhesive tape isreleasably attached to the connector about the plug, holding the plug tothe connector.

Further, the present invention relates to a sleeve, the first end ofwhich fits about a ferrule of a telecommunications connector with theend face of the ferrule within an axial opening of the sleeve. A plug isinserted into a second opposing end of the sleeve. The sleeve fitsclosely about both the ferrule and the plug to prevent entry of airbornecontaminants into the axial opening through either end.

Still further, the present invention relates to a body including anaxial opening with a first end and an opposing second end. A ferrule ofa fiber optic connector is placed within the axial opening through thefirst end so that a polished end face of the ferrule is within the axialopening. A removable adhesive sealing member is placed over the secondend of the axial opening. The body fits about the ferrule to prevententry of airborne contaminants into the axial opening through the firstend and the sealing member prevents entry of airborne contaminants intothe axial opening through the second end.

The present invention also relates to a method of sealing atelecommunications connector against airborne contaminants comprisingterminating a fiber optic cable with a fiber optic connector in a cleanenvironment protected against airborne contaminants. An end of anoptical fiber within the cable is terminated at a polished end face of aferrule of the connector. Within the clean environment, a seal is placedabout the ferrule to protect the polished end face of the ferruleincluding the end of the optical fiber against airborne contaminants.The connector is then transported to a location where a fiber opticcommunications linkage is desired. The seal is then removed from theconnector and the communications linkage is made without cleaning theend face of the connector.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of the description, illustrate several aspects of the invention andtogether with the detailed description, serve to explain the principlesof the invention. A brief description of the drawings is as follows:

FIG. 1 is a perspective view of a telecommunications connector clamshellprotective device according to the present invention.

FIG. 2 is a side view of the protective device of FIG. 1 with the lidclosed and the foam sealing blocks and the telecommunications cable andconnector indicated with dashed lines.

FIG. 3 is a side view of a second embodiment of a telecommunicationsconnector protective device according to the present invention with thelid closed and the foam sealing blocks and the telecommunications cableand connector indicated with dashed lines.

FIG. 4 is a perspective view of a third embodiment of atelecommunications connector plug protective device according to thepresent invention.

FIG. 5 is a cross-sectional view of the protective device of FIG. 4mounted on a fiber optic connector.

FIG. 6 is a partial cross-sectional view of the protective device ofFIG. 4.

FIG. 7 is a side view of a fourth embodiment of a telecommunicationsconnector protective device.

FIG. 8 is a side view of a fifth embodiment of a telecommunicationsconnector protective device.

FIG. 9 is an end view of the protective device of FIG. 8.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary aspects of the presentinvention which are illustrated in the accompanying drawings. Whereverpossible, the same reference numbers will be used throughout thedrawings to refer to the same or similar parts.

When a telecommunications connector is installed in an operationalenvironment, dust and other contaminants may degrade the level of signalthat is transmitted through the connector and the communications circuitto which the connector is attached. These contaminants may be introducedinto the communication circuit at any time from when the connector isassembled (such as in a factory) to when the connector is insertedwithin a mating adapter (such as in an interconnect panel or otherconnection device). By assembling connectors in a relatively cleanfactory environment and providing a secure and removable shield for theconnector, the potential for contaminants being introduced into such acommunications circuit may be minimized.

Referring now to FIG. 1, a telecommunications connector 16 is shownwithin a clamshell protective device 10. Clamshell device 10 includes abox 12 and a lid 14 hingedly mounted to each other by hinge 13.Alternatively, box 12 and lid 14 may be separate elements without hinge13 or other connection extending between them. Connector 16 is mountedto the end of and terminates a telecommunications cable 18. As shown,connector 16 is an optical fiber connector commonly referred to as an FCconnector and cable 18 is an optical fiber cable including a strand ofoptical fiber terminated at a ferrule 17. Other styles and formats ofoptical fiber connectors and high speed copper connectors are alsocontemplated within the scope of the present invention. The amount ofdata that may be transmitted through any of these connector types may beimpeded by contaminants and use of a protective device such as device 10may provide protection from the introduction of such contaminants.

Connector 16 is received within a recess 20 of box 12. A slot 22receives cable 18. Cable 18 also passes across a first foam block 24mounted within recess 20 adjacent slot 22. Block 24 may be formed of adeformable resilient foam to permit block 24 to conform the diameter ofcable 18 and prevent entry of contaminants into recess 20 through slot22. A mating foam block 26 is included on lid 14 which cooperates withblock 24 to assist in sealing around cable 18. Alternatively, either ofblocks 24 or 26 may be made of a material capable of conforming to thefull diameter of cable 18 so that the other mating block may be formedof a relatively non-deformable material. The non-deformable block may beintegrally formed as part of either lid 14 or box 12 so that fewercomponents are needed to assemble device 10.

Block 26 is within a mating recess 32 of lid 14. Recess 32 includesperimeter walls 34 extending about lid 14. Walls 34 engage matingsurfaces 30 of box 12 about recess 20 and cooperate to seal recesses 32and 20 against contaminants reaching connector 16 when device 10 isclosed as shown in FIG. 2. Walls 34 and mating surfaces 30 may be snapfit with each other when lid 14 is mated with box 12, as shown in FIG.2, and the snap fit may be close enough to prevent entry ofcontaminants. Alternatively, walls 34 and mating surfaces 30 may bebonded to each other, such as with glue, heat sealing, ultrasonicwelding or other techniques, to provide additional protection againstthe entry of contaminants. FIG. 2 also shows foam blocks 24 and 26 ofprotective device 10 of FIG. 1 cooperating to seal about cable 18 toprevent entry of contaminants into device 10.

Adjacent mating surfaces 30 about recess 20 are flanges 36. Adjacentperimeter walls 34 about recess 32 are flanges 38. As an alternative tobonding perimeter walls 34 to mating surfaces 30, flanges 32 and 34 maybe bonded to each other, such as with glue, heat sealing, ultrasonicwelding or other techniques.

Referring now to FIG. 3, a second embodiment of a protective device 110is shown with a lid 114 and a box 112 connected by hinge 13. Device 110differs from device 10 in that box 12 and lid 14 are approximately equalin depth, whereas box 12 is substantially deeper than lid 14. Recess 32of lid 14, as shown in FIG. 2, may only extend to the depth needed todefine perimeter walls 34. Recess 132 of lid 114 extends to a greaterdepth than required to define perimeter walls 34, as shown in FIG. 3. Asshown in FIG. 2, connector 16 is positioned substantially within recess20 of box 12 and only a small portion of connector 16 extends withinrecess 32 of box 14. As shown in FIG. 3, connector 16 extends withinboth recess 132 and a recess 120 of box 112 approximately equally. Apair of foam blocks 124 and 126 are positioned adjacent an end of device110 opposite hinge 13 to permit entry of cable 18 into device 110 and toseal about cable 18 against the entry of contaminants.

While devices 10 and 110 protect an end of cable 18 terminated atferrule 17 from contaminants as described above, these devices alsoprovide some protection from impact or other physical damage that mayadversely affect the ability of connector 16 to interface with otherelements of the telecommunications circuit. As is well known in theprior art, telecommunications connectors such as connector 16 includefeatures which mate with adapters or other components and which mayprovide a secure and sealed interface for the transmission of signals,either optical or electrical. These mating features also need to beprotected from contaminants as well as from physical damage. Devices 10and 110 provide protection to these mating and locking features ofconnector 16 as well as to ferrule or cable termination 17.

Referring now to FIGS. 4 to 6, a plug protective device 52 forprotecting an end face 50 of ferrule 17 of telecommunications connector16 is shown. Plug 52 includes a body 58 and a larger diameter portion 60defining a shoulder 64 between. An inner cylindrical opening 56 isdefined within plug 52 for receiving and sealing about ferrule 17. Whenplug 52 is positioned about ferrule 17 as shown in FIG. 5, the sealbetween an inner wall 59 of body 58 within a cylindrical cavity 56 formsan air-tight seal, so that air is compressed within cavity 56 betweenend face 50 and an inner end wall 66. To prevent this compressed airfrom forcing plug 52 from about ferrule 17 and allowing contaminants tocome into contact with end face 50, a tape 54 is positioned about plug52 to hold plug 52 to connector 16. Tape 54 may include an anti-tamperfeature which will indicate of tape 54 has been removed and replaced orotherwise disturbed. If this anti-tamper feature indicates that tape 54has been disturbed, this may indicate the seal between plug 52 andferrule 17 has been broken and that end face 50 may have been exposed tocontaminants. Tape 54 may also be mounted to connector 16 and plug 52with a tail 55 to facilitate the removal of tape 54 and plug 52 fromconnector 16.

As shown, ferrule 17 is inserted within cavity 56 of plug 52 through anopening 62. To assist in the alignment and entry of ferrule 17 intocavity 56, a tapered entry 63 into opening 62 may be provided. At theinner end of taper 63, adjacent inner wall 59, a smaller diameter ledge68 is formed. It is anticipated that plug 52 will be made of a resilientdeformable material such as a thermoplastic elastomer. Ledge 68 shouldpromote the formation of an airtight seal about ferrule 17 by deformingto closely match the outer surface of ferrule 17 as plug 52 is mountedto connector 16. Ledge 68 may also serve to brush off surfacecontaminants from the outer surface of ferrule 17 as plug 52 is placedabout ferrule 17 and ensure that these contaminants do not enter cavity56. Shoulder 64 provides a finger hold to aid in the removal of plug 52from connector 16.

Referring now to FIG. 7, a fourth embodiment of a protective device 70includes a plug 72 and a sleeve 74. A first end 82 of sleeve 74 is sizedto be received about ferrule 17 of connector 16 so that end face 50 iswithin an axial opening 75 of sleeve 74. Axial opening 75 is defined byan interior wall 73. In FIG. 7, axial opening 75 is shown enlargedgreater than the diameter of ferrule 17 for clarity. However, axialopening 75 is sized to fit closely to ferrule 17 to prevent contaminantsfrom passing through first end 82 along ferrule 17 to reach end face 50.As shown, axial opening 75 is consistent in diameter from first end 82to a second end 84. Plug 72 includes a shaft 78 which similarly sized toferrule 17 and is inserted through second end 84 into axial opening 75.Shaft 78 includes a mating portion 76 sized and shaped to approximatethe polished shape of end face 50. Mating portion 76, as shown, isconcave and forms a contour to match the polished convex shape of endface 50. Mating portion 76 is shown offset from end face 50 for clarityin FIG. 7. However, in use, mating portion 76 will be in close proximityor contact with end face 50 to further provide protection againstcontaminants reaching end face 50.

Other polish profiles for end face 50 are known and it is anticipatedthat mating portion 76 may be shaped as appropriate to match these knownpolish profiles. It is also anticipated that mating portion 76 may beshaped to match new polish profiles that may be developed, within thescope of the present invention. Plug 72 also includes an enlarged end 80opposite shaft 78. Enlarged end 80 provides a finger grip for removingdevice 70 from ferrule 17 of connector 16.

As shown, mating end 76 is offset from end face 50 for clarity. However,end face 50 and mating face 76 would be positioned directly adjacenteach other so that mating face 76 may block contaminants from reachingend face 50. As axial opening 75 is uniform in diameter and shaft 78 issimilarly sized to ferrule 17, contaminants are prevented from enteringaxial opening 75 through second end 84 as well.

Referring now to FIGS. 8 and 9, a fifth embodiment of a protectivedevice 90 includes a body 96 with a flange 94 at a second end 104. Body96 includes an inner wall 98 which defines an interior opening 100extending between a first end 102 and second end 104. Interior opening100 is sized to be received about ferrule 17 so that end face 50 iswithin opening 100 and inner wall 98 fits closely about ferrule 17 toprevent contaminants from entering opening 100 through first end 102.With such an air-tight or near air-tight seal between ferrule 17 andinner wall 98, second end 104 of body 96 is open to permit ferrule 17 tobe inserted within opening 100 and allowing displaced air to escape.Once ferrule 17 has been placed within opening 100, an adhesive member92, such as tape, is then placed across end 104 to provide an air-tightseal of second end 104 and prevent contaminants from entering opening100 through second end 104.

As shown, member 92 extends beyond a flanged portion 94 of body 96, sothat member 92 may be removed to permit protective device 90 to bewithdrawn from ferrule 17. Flanged portion 94 provides a finger grip toaid in the removal of body 96 from ferrule 17. Alternatively, member 92could be sized to more closely match the size and shape of flangedportion 94 with a single tab extending beyond flanged portion 94 topermit removal of member 92.

While several embodiments of protective devices have been describedherein, a generalized procedure for protecting telecommunicationsconnectors from airborne contaminants applicable to many of theseembodiments is within the scope of the present invention as well. Thisgeneralized procedure begins with a fiber optic cable being terminatedwith a fiber optic connector in a clean factory environment. An opticalfiber within the cable is positioned within a ferrule of the connectorand an end face of the ferrule and the end of the fiber adjacent the endface are polished to the desired polish profile. Once the end face hasbeen finished and before the connector is removed from the clean factoryenvironment, a seal is applied to the connector to protect the end facefrom airborne contaminants.

The protection procedure also includes transporting the protectedconnector to a location where a fiber optic communications linkage isdesired. This location may be in an environment where the air is not asprotected from airborne contaminants as the factory environment.Further, during transportation or storage, it is desirable that the endface of the connector be protected from airborne or other contaminantsas well. Once at the location of the desired telecommunicationsconnection, the seal may be removed from the connector and the linkagemay be completed without the need for cleaning of the end face in thefield.

The creation of the seal about the end face and removal of the sealprior to making the linkage may be performed by the methods and devicesdescribed above.

The embodiments of the inventions disclosed herein have been discussedfor the purpose of familiarizing the reader with novel aspects of thepresent invention. Although preferred embodiments have been shown anddescribed, many changes, modifications, and substitutions may be made byone having skill in the art without unnecessarily departing from thespirit and scope of the present invention. Having described preferredaspects and embodiments of the present invention, modifications andequivalents of the disclosed concepts may readily occur to one skilledin the art. However, it is intended that such modifications andequivalents be included within the scope of the claims which areappended hereto.

1-15. (canceled)
 16. A fiber optic connector assembly comprising: afiber optic connector mounted to an end of and terminating a fiber opticcable, the fiber optic connector including a ferrule holding an opticalfiber from the cable, the ferrule including an end face; a plugextending from a closed end to an open end, the open end of the plugbeing configured to fit about and engage the ferrule of the fiber opticconnector, the plug being positioned about and engaging the ferrule toreceive at least a portion of the ferrule within the open end to sealthe end face of the ferrule from air-borne particles; and an adhesivetape releasably attached to the connector about the plug to hold theplug to the connector, the adhesive tape extending from a first side ofthe fiber optic connector, about the closed end of the plug, to anopposite side of the fiber optic connector; wherein the plug includes abody defining an inner cavity with an opening for insertion of theferrule within the cavity, the opening including a tapered entry and aledge positioned between an inner end of the tapered entry and an innerwall of the cavity, the ledge defining an opening smaller than thediameter of the ferrule and the cavity having a diameter generally thesame diameter as the ferrule.
 17. The assembly of claim 16, wherein theplug is made from a thermoplastic elastomer and deforms to fit about theferrule.
 18. (canceled)
 19. The assembly of claim 16, wherein the bodyof the plug includes a larger diameter end opposite the opening and ashoulder is defined between an outer surface of the body and the largerdiameter end. 20-27. (canceled)